Apparatus for producing hydrochloric acid



H. M. LASHIRI APPARATUS FOR PRODUCING HYDROCHLORIC ACID.

Patented Apr. 6, .1920.

2 SHEETS-SHEET I.l

APPLICATION FILED JULY I3,II9I 7.

A T A I-Iilll 'H. M. LASHER. APPARATUS FOR PRoDUclNG HvnRocHLoRlc A01-.'

WHW" LE "j" 3 9'7' l Patented Apr. 6,1920.

HENRY 1VL LASI-IER, OF KANSAS CITY, KANSAS, ASSIGNOR TO THE KANSAS CITY REFINING COMPANY, OP KANSASv CITY, KANSAS.

APPARATUS FOR PRODUCING HYDROCHLORIC ACID.

Specification of Letters Patent.

Patented Apr. 6, 1920.

Original application led May 9, 1916, Serial No. 96,430. Divided and this application filed July 13, 1917.

Serial No.

To all whom t may concern.'

Be it known that I, HENRY M. Lasiinn, a citizen of the United States, residing at Kansas City, in the county of lVyandotte and State of Kansas, have invented certain new and useful Improvements in Apparatus for Producing Hydrochloric Acid, of which the following is a specification, reference being had therein to the accompanying draw# ing.

My invention relates to apparatus fo-r the production of hydrochloric acid and more particularly to apparatus especially adapted to the utilization of sludge acid for the productio-n of hydrochloric acid gas and its absorption by water to produce what is commonly known as liquid hydrochloric acid. The present invention is a division of my copending application Serial No. 96,430, filed. May 9, 1916.

My invention is illustrated in the accompanying drawings in which- Figure 1 is a diagrammatic sectional view showing the still, the purifying tower and the receiving tank, with their several connected and auxiliary parts forming a complete system.

Fig. 2 is a longitudinal and partly sectional view of the receiving tank, showing the arrangement of the distributing pipe for the incoming gas. Y

Fig. 3 is a view similar to Fig. 1 showing a modified arrangement of the still and the purifying tower, with a special form of absorber.

Referring to the drawings, 1 represents a lead lined pan or receptacle, the top of which is closed by an acid proof tile arch Q, closed except for doors 3, used for the purpose of Vfilling the container l. This combination forms a still, supported upon bric-k walls el, as by means of ears 5 in the usual manner, said walls inclosing a furnace 6 by means of which heat may be applied to the pan or receptacle 1. At the bottom of the pan a drain pipe 7 is provided with a plug 8 controlled preferably from above as for example by means of a resistant rope or chain 9. This drain pipe is used to draw off the residuum at the end of each run. Entering the still through the sides, and with ends above the pan 1, are two feed pipes 10 and 11, the first of which is used to convey water into the still, and the second to convey sludge acid. Each of these pipes isv provided with a suitable cut-off valve, and they may be fed from storage tanks or other suitable sources of supply, so as to raise the efficiency of operation, and make it as nearly continuous as possible.

Leading out of the upper part of the still is an acid proof tile pipe 12 thro-ugh which the gases are conducted to the purifying tower 13. This tower is composed of acid proof tile, with an inlet 14V at the bottom' and an outlet 15 at the top. It is divided in any suitable manner as by means of acid re.- sisting screens 16 and 17 into three chambers, 18, 19 and Q0. The chamber 1S is vacant, and is provided at the bottom with a drain pipe 21 fitted with a suitable cock. This chamber 18 catches all impurities which are trapped back from the upper purifying 4chambers 19 and 20. The chamber'19 is packed with lumps of sodium chlorid and has the upper part left clear, so as to make a space between the chambers 19 and 20. This is necessary, in order to prevent impurities which have been taken out by the medium in chamber 19, from being carried up into chamber 20 by means of capillary attraction. Chamber 20 is also preferably provided with a clear upper space, although this depends somewhat upon the arrangement of the outlet 15, the object being to prevent impurities being carried over into the outlep pipe.

From the outlet 15, an acid proof pipe 22 leads through a suitable coupling and connections to the acid or receiving tank ")3 The pipe 22 enters this tank from above, and has suspended from it, one or more, preferably a plurality of longitudinal pipes perforated with small holes whose aggregate area is equal to the total area of the pipe 22. The tank Q3 is partly filled with water, the quantity of water depending upon conditions, but in any case suflicing to fully cover the pipe system Z2- 24s. The tank is provided with a manhole opening '2G for cleaning purposes, this being fitted with a tightcover, whereby thc opening may be conipletely sealed in operation. The acid proof pipe 25 leaves the lower part of the tank, for drainage purposes, and an iron pipe 57 passes out of the upper portion of the tank for the purpose of conducting away the waste gases.

The use and operation are as follows: The sludge acid is mixed with sodium chlorid in the proportion of fifty parts by weight acid to fifty parts by weight of sodium chlorid and this mixture is then diluted with about ten parts by weight of water. ln making this mixture in the pan 1, the pipes 10 and 11 are used to introduce the acid and the water respectively andthe doors 3 to intro-Y duce the sodium chlorid. Heat is then produced in the furnace to raise the temperature of the mixture in the container to a point not exceeding the boiling point of sulfuric acid, that is to say 284O C. The addition of the water to the mixture causes the asphaltumand tarry matters to be liberated and to rise to the surface of the solution and float as a scum thereon. lt is necessary that this take place and that the mixture and heat be as stated because if any considerable portion of the asphalt and tarry matters is left suspended, since these compounds are composed mostly of carbon, and since carbon is a reducing agent, the carbon thus held in supension would unite chemically4 with the oxygen in the sulfuric acid and produce free carbon dioxid and sulfur dioxid. The result would be to consume the sulfuric acid without appreciable action upon the sodium chlorid and formation of hydrochloric acid. Heating of the mixture continues, the usual reaction takes place between the sulfuric acid and the sodium chlorid, whereby hydrochloric acid gas is liberated and passes out of the top or dome of the still through the pipe 12 and into the lowest chamber 18 of the vpurifying tower 13. As the gas rises and is forced upward, it passes from the lowest chamber 18 into the mass of sodium chlorid lumps resting on the screen 16 in the cham ber 19. The heaviest and coarsest impurities, such as asphalt and tar carried over by the rush of gas, are separated immediately, and together with the drainage efrom the upper chamber, collect in the bottom of the lowest chamber 18 from which they are drained off from time to time through the pipe 21 as the process goes on. In passing upward in succession through the chambers 19 and 20, the acid gas is deprived of the vapors and particles of asphalt, tar and oil which have been carried over with it through the pipe 12, the charcoal which is mingled with the sodium chlorid in the chamber 20 acting as an absorbent of said matters, and the sodium chlorid in both chambers coincidently acting to change any of the sludge carried over, and to complete the reaction and purication initiated in the still.

The acid gas thus purified is carried over from the chamber 20 through the outlet 15 and the lead pipe 22 into the acid tank 23, where it passes through the pipes 24 and is distributed to all the little openings in said pipes, through which it escapes and is absorbed into the water which covers them. rlhe process is continued until a solution of any desired strength is produced, and this may be concentrated thereafter, or pure acid obtained therefrom, in any known manner. The solution is finally drained off from the tank 23 through the pipe 25.

lThe residuum left in the pan "1 by this process, after complete distillation.V consists of a solution of sulfate with a floating scum, which scum is largely composed of asphalt, tarry and fatty matters. The sodium sulfate solution is drawn out of the bottomfof the receptacle 1 -after which it may be concentrated by evaporation. After the sodium sulfate has thus been extracted, the scum component is drawnV off, if necessary by washing out, through the pipe 7. It may be treated for the recovery of the several constituents of which it is composed, if de sired, or may be used with or without further purifying, for road binding material, or otherwise.

In F ig. 3, the still and the purifying tower 13 are substantially the same as in Fig. 1, but from the outlet 15 of the tower, the absorbing apparatus is different. i This latter consists of a vertical pipe 26 connected at its lower end to the absorber 27 which is fitted with baffle plates or partitions 28 or 29 extending alternately from the bottom and the top, and so related to each other that liquid flowing through the absorber will be forced to pass up and'down between the baffles, and gas vflowing through the same compartments will follow the same course and thereby will be'brought into intimate contact with the water and be forced therethrough, so as to be absorbed thereby. The discharge end 30 of the absorber 27 is connected to an inlet 31 to a primary absorbing tower 32 divided into three compartments, the upper one 33 being filled with small pieces of acid-proof earthenware, the middle one 34 being a gas and water chamber or separator, and the lower one 35 a receiving chamber for the concentrated acid solution. Chambers 34 and 35 are separated by a plate 36 having a central opening 37 with a high flange surrounding it, to prevent drainage of water from chamber 34 into chamber 35, while permitting the free passage of gas upwardly from chamber 35 into chamber 34. Water is in-V troduced through a pipe 39 and a spray 40 controlled by the valve 41, into the top of the chamber 33,'through which it trickles down over the surfaces of the pieces of earthE enware until it reaches the chamber 34, being exposed over a very large superficial area, while flowing, to the action of the acid gas rising through the chamber. Onk reaching the chamber 34, the liquid which by that time is already a dilute acid, is prevented from reaching the opening 37 by the baflle plate 38, which sheds all` the liquid over towardY a'n outlet 42 of the chamber 34. From this outlet an acid proof pipe 43 leads across through a U-trap 44 to an inlet 45 in the down pipe 26.

The operation of this modified form of apparatus is as follows: After being purified in the tower 13, the acid fumes pass down into the pipe 26 and being prevented from passing through the pipe 43 by the liquid filled trap 44, are forced to traverse the absorber 27, as indicated by the upper line of arrows therein. Liquid is simultaneously circulated through this absorber, its superior gravity causing it to flow along the bottom as indicated by the lower line of arrows. The baffles 28 and 29 force the gas into intimate contact with the water, thereby producing a very high percentage of absorption by the time the mixed gas and water reach the outlet 30`of the absorber. The gas passes upwardly through the opening 37, and around the inclined baffle plate 38 and finally? rises through the mass of earthenware 33 and is further absorbed by the incoming water from the spray 40. What is left of the gas after passino' the spray may escape or may be received and retained in any appropriate manner if desired.

The water from the spray 40 passes down through t-he earthenware into the chamber 34 through the pipe 43 and trap 44 into the inlet and so down through the pipe 26 into the `absorber and back to the chamber 35 from which as concentrated acid it is drawn ofi through the pipe 46 into the final l receiving tank 4 Having thus described my invention what I claim and desire to secure by Letters Patent is:

1. An absorber comprising an elongated chamber arranged horizontally, upper baffies extending downwardly from the to-p of said chamber, and lower baffles extending upwardly from the bottom of said chamber, said upper and lower battles being arranged alternately and extended approximately to a common horizontal line.

2. In apparatus for making hydrochloric acid, a still, a gas conveyer, and an absorber provided with baflie plates, with means to produce a circulation of water mixed with the gas Jfrom the conveyer, through the absorber into a receiving chamber.

3. In appar-atus for making hydrochloric acid, a still, a pipe line Jfor conveying acid gas from said still, an absorber connected with said pipe line and comprising a conduitl containing a succession of oppositely extending and alternating baflies, a primary tower containing fragmentary material in Vmass, with means to supply water to the upper part of saidmass, alsocontaining a middle chamber for receiving the acidulated water as it trickles through said mass, and a lower chamber connected to receive the final dilute acid from the absorber, the lower and middle chambers of the primary tower being connected for the passage of' gas from the lower to the middle chamber and from the 'middle chamber upward through the mass of fragmentary material, but arranged to prevent the passage of liquid downwardly fromthe middle chamber into the lower chamber, and a pipe connection constructed of acid-proof material, extending from the lower part of the middle chamber in the primary tower to the inlet end of the absorber, the course of the liquid beingl through the primary tower, from the middle chamber thereof through the pipe line to the inlet end of the absorber, through the absorber and back into the lower chamber of the primary tower whence it may be drained off int-o any suitable container.

4. In apparatus for making hydrochloric acid, a source of gaseous fiuid, a pair of absorbers connected with said source, means for directing the flow of gas through said absorbers in sem'atz'm, and means for directing the flow of'a liquid through said absorbers in scrz'atim, in opposition to the iiow of gas in one absorber and in the same direction with the fiow of gas in the other absorber.

5. In apparatus for making hydrochloric acid, a source of'y gaseous fluid, a plurality of absorbers, means for directing the flow of gas through said absorbers 'm serz'atim and in a given direction, and means for directing the flow of a liquid through said absorbers first in one absorber in opposition to the flow of gas and then in another absorber in the same direction as the flow of gas.

6. In apparatus for making hydrochloric acid, a source of gaseous fluid, a pair of absorbers, means for directing the flow of gas from said source first through one absorber and then through the other in sert'- atz'm, means for directing the flow of a liquid through the last absorber in opposition to the flow of gas, means for directing the flow of liquid from said last absorber through the first absorber in the direction of flow of the gas, and means for trapping the liquid after it has traversed the said first absorber.

In testimony whereof I afliix my signature.

HENRY M. LASHE'R. 

